Ignition system distributor head



g- 3, 1954 J. 1.. RABALLO ET AL IGNITION SYSTEM DISTRIBUTOR HEAD Filed Dec. 2, 1952 INVENTOR. JOHN L.RABALLO AND B WILLIAM M. GETTY W M flTfm/wy Patented Aug. 3, 1954 UNITED STATES PATENT OFFICE IGNITION SYSTEM DISTRIBUTOR HEAD cent to Xum Speegle Application December 2, 1952, Serial No. 323,622

5 Claims. 1

ihe invention relates to internal combustion engine controlling apparatus and more particularly to an improved construction for an ignition distributor head of the type having a multiplebreal; contact system.

An object of our invention is to provide an improved mounting for the timing contacts of an internal combustion engine distributor head which is practical, eficient and inexpensive in construction.

A further object of the invention is to provide circuit breaker mounting for a multiple-break distributor head of an internal combustion engine which may be easily and conveniently installed as a replacement in distributor heads of the type now generally provided with a single set of circuit controlling contacts.

A. further object of the invention is to provide an improved type of frictionless ball bearing mounting for the circuit breaker carrying plate of a distributor head of conventional design.

Qther objects and advantages will be in part evident to those skilled in the art and in part pointed out hereinafter in connection with the accompanying drawing herein and is shown by way of illustration and not of limitation a preferred embodiment of our invention.

in the drawing- Figure 1 is a plan view of a distributor head of a conventional design showing our invention installed therein, and

Figure 2 is a sectional view taken along line IIII of Figure 1, looking in the direction of the arrows.

The timing system for the firing of the cylinders or" multi-cylinder internal combustion engins as now installed on stock cars delivered from the factory are generally provided with a single set of timing contacts that are operated by a timing cam driven from the engine shaft in a manner well understood in the art. In order to improve the timing and to provide for a more intense spark at the spark plugs, it has been proposed to employ two sets of timing contacts the lines of the system disclosed in a patent to 5 Marion Mallory issued April 21, 1936, identified by number Re. 19,937 and entitled Engine Ignition System. The advantages of this arrangenow well understood by those skilled in the art.

In the Mallory arrangement there is no provision for moving the circuit controlling contacts with respect to the timing cam of the distributor head except by moving a portion of the housing. However, more recently there has been developed a number of mountings for the circuit breaker supporting plates of these distributor heads wherein ball bearings have been employed at the outer perimeter of the circuit breaker supporting plate. This involves a complicated construction and entails an expensive modification of the distributor head housing which is not satisfactory and can only be installed at the factory where the distributor head is manufactured.

it is therefore an important and further object of our invention to provide a multi-circuit breaker arrangement for distributor heads of conventional type in which the circuit controlling contacts may be installed and/or replaced with simple tools in any ordinary repair garage. We have by our invention, provided a movable support for the circuit breaker carrying plate which is mounted directly upon the bronze bushing that forms a part of the distributor head as a support for the timing cam shaft. With this arrangement the advantages of the anti-friction or ball bearing supports are retained in a more practical and less expensive manner and in direct concentricity with the timing cam, a condition which is difficult to obtain where the circuit breaker supporting plate is journaled within and upon the housing of the distributor.

For a better understanding and more detailed description of our invention reference is now had to the accompanying drawing, wherein the distributor head housing, designated by the nu ineral it, is shown as having a cup-like recess ii at its upper end and 2. depending circular portion it! within which a timing cam supportsh it it is journaled. The timing cam shaft is a drive engaging E4 at its lower end and a timing cam near its upper: end. The shaft 53 journal :1 at its lower end within a .-bL-,sliin" it carried by the depending portion l2 of the c stributor head housing and at its upper end it is journaled within a relatively large tubular bronze bushing il' which extends upwardly into the cup-like recess i of the housing 5 bushing ii is conventional and is at the present time relied upon to provide both a journal for the shat l3 and also a step and radial bearing upon which the present day distributor head circuit breaker supporting plates are directly mounted.

In our arrangement as distinguished from the prior art, we employ an inner cylindrical and steel ball race it, that is mounted with a drive fit upon the bronze bushing ll. Intermediate the ends of the ball race l8 there is an outwardly extending annular flange l9, which, in combination with the cylindrical portion of the cylindrical portion of the ball race 18, provides spaced and oppositely exposed ball bearing raceway surfaces that extend at right angles to each other against which an upper and lower set of ball bearings 20 and El respectively engage. In this arrangement it will be seen that the ball bearings 2i! and 21 make a two-point contact with the inner raceways i and 19. To complete this assembly we employ a circuit breaker supporting plate 22 that is composed of upper and lower parts 23 and 24 which are secured together as a unit in any suitable manner as for example by means of rivets. 22'. The plates 23 and 2e are flared outwardly in opposite directions and are formed at their inner perimeters, as at 25 and 25, so as to provide arcuate ball bea' engaging raceways which when installed provide a semi-circular bearing surface which firmly engages with the two sets or" ball bearings 24} and 12 i.

Secured to the supporting plate 22 there are two oppositely arranged contact supporting members 2? which carry stationary contacts 28 and 2S, and also movable contacts so and 3!.

These contact support members ii are here shown as secured upon the supporting plate 22 by a slot and screw arrangement so that earn engaging members 32 and (is carried thereby and which control the moving contacts is and (it may be properly adjusted with respect to the timing cam i5. As set forth in the above identified Mallory patent, the cam engaging members 32 and 33 are adjusted so as to provide for an overlapping in the opening and/or closing periods of the circuit controlling contacts 23, so and 29, 3!.

In addition and in order to advance and/or retard the operation of the timing cam with respect to these circuit controlling contacts the distributor head housing is here shown as having an extending external flange it upon which a vaccum controlled diaphragm mechanism 35 is mounted. The diaphragm mechanism 35 in this arrangement has a diaphragm 36 that is connected at one side to the contact supporting plate 2 of the distributor head by a tie rod 3? and at its other side this diaphragm SE is exposed to a vacuum zone of the internal combustion engine so that the movements of the contact supporting plate relative to the timing cam is is controlled by operating conditions of the internal combustion engine. Because of this latter operation the problem of mounting the circuit breaker supporting plate 22 becomes important, as it is imperative that the contact supporting plate be mounted to move without friction and in response to the slightest change in the vacuum produced by the internal combustion engine during its operation.

An important advantage of our invention is that it is of such construction that it may be mounted in the majority of automobiles, now in use and as at present manufactured, as a substitute for the conventional single circuit breaker arrangement by a simple, convenient and inex pensive operation and it is to meet the demand for this improvement in the timing circuit to the conventional internal cornubstion engines that our present invention has been developed.

In the arrangement employing the double breaker contact as here described and shown in the drawing we have found it more practical to mount the condenser, designated by the numeral 38, externally of the housing it, but where our invention is employed with a single contact breaker the condenser may be mounted upon the breaker late and within the housing It in the conventional manner.

While we have, for the sake of clearness and in order to disclose the invention so that the same can be readily understood, described and illustrated a specific form and arrangement, it is to be understood that the invention is not lllllited to the specific form disclosed, but may be embodied in other forms that will suggest themselves to persons skilled in the art. It is believed that this invention is new and it is desired to claim it so that all such changes as come within the scope of the appended claims are to be considered as part of this invention.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

1. In a circuit breaker mounting in the distributor head of an ignition system, the combination of a distributor head having a cup-like housing, a cylindrical bushing extending centrally and upwardly into said housing, a shaft journalled within said bushing having a timing earn upon its extending end, said timing earn abutting the end of said bushing as a thrust bearing for said shaft, a cylindrical ballrace member having a central flange with ballraces at opposite sides thereof, and. a breaker supporting plate, comprising two substantially similar annular plate-like members having their inner perimeter-s flared in opposite directions to provide spaced and opposed raceways, whereby when assembled upon said cylindrical bearing member with ball bearings about its raceways said plate-like members will form a freely movable support for a circuit timing breaker.

2. In an ignition system distribtor head, the combination of a housing, a cylindrical bushing extending vertically into said housing, a cam shaft journalled in said cylindrical bushing and having a driving gear at its outer end, a timing cam secured to the other end or" said shaft and disposed Within said'housing and engaging the end of said cylindrical bushing as a thrust bearing, a cylindrical ballrace member mounted upon the extending end of said cylindrical bushing with a drive fit and having an outwardly extending annular flange intermediate its ends dividing two spaced ballraces at opposite sides thereof, and a circuit breaker supporting incinber comprising two annular platedike members having their inner perimeters flared in opposite directions to form ball rec-aways, annular plate-like members being permanently secured together with their raceways at opposite sides of the annular flange upon said cylindrical ballrace member, whereby upon assembly said inner ballrace and said circuit brea. supporting member will form a unitary s'ructure.

3. In an ignition system distributor head, the combination of a distributor housing having a cup-like chamber at its upper a depending shaft supporting portion, a cam shaft journalled centrally in the dependi: g portion of said housing, a cylindrical bushing forming a journal for said shaft carried by said housing and extending upwardly into cupe chw .ber, a timing cam at the upper end of supported upon said bushing a thrust bearing, an inner cylindrical ballrace forming member mounted with a drive fit upon extending end of said bushing and having an annular flange intermediate its ends forming a common part of two ball bearing raceways, a timing contact supporting member adapted and arranged to be mounted with ball bearings upon the raceways of said cylindrical ballrace forming member, said contact supporting member being formed of two annular plate-like members each having a ballrace at its inner perimeter cooperating with ball bearings disposed upon the ball raceways formed by the annular fiange upon said ballrace forming member, whereby said inner ballrace forming member and said timing contact supporting member may be removed and replaced upon said cylindrical bushing as a unitary assembly.

4. In an ignition system distributor head, the combination of a housing having a cup-like recess at its upper end and a depending shaft supporting portion, a cylindrical bushing mounted with a drive fit within said housing and extending upwardly into the cup-like recess thereof, a cam driving shaft extending centrally through said cylindrical bushing having a driving gear at its lower end, a timing cam at the upper end of said shaft engaging the end of said bushing as i a thrust bearing, a cylindrical ball race member mounted with a driving fit upon the extending end of said bushing having an outwardly extending flange intermediate its ends forming spaced ball bearing raceways, a movable contact supporting member formed of two plate-like members each one of which provides one of two spaced and oppositely disposed raceways at their inner perimeters when secured together, a series of ball bearings positioned between the raceways of said tubular ball race forming member and said plate-like members, and circuit controlling contacts mounted upon said contact supportiii ing member in cooperating relation with said timing cam.

5. In an ignition system distributor head, the combination of a housing having a central shaft supporting portion, a cylindrical bushing mounted with a drive fit within the shaft supporting portion and extending upwardly into said housing, a timing cam supporting shaft journaled in said cylindrical bushing, a driving gear at the lower end of said shaft, a timing cam secured to the upper end of said shaft and engaging the upper end of said bushing as a thrust bearing, an inner ball race forming member mounted with a driving fit about the extending end of said bushing having an outwardly extending flange intermediate its ends forming spaced ball bearing raceways, and a plate-like timing contact supporting member disposed in a plane transverse to the axis of said shaft having opposed and spaced raceways adapted to engage ball bearings positioned upon the spaced raceways of said inner ball race forming member, said timing contact supporting member being formed of two substantially identical annular plate-like meinbers having cupped inner perimeters disposed in opposed relation adapted and arranged when secured together to engage ball bearings at opposite sides of the flange upon said inner ballrace forming member with freedom of rotary movement.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,096,294 Bryant Oct. 19, 1937 2,270,982 Vanderpoel et a1. Jan. 27, 1942 

